Thank you for trying, then. Let's see if I'm getting this right:
There are little "tasks" that are given by the computer-controlled characters and basically matter to you alone, with no influence on the game world -- and then there're bigger adventures that however aren't tightly plotted and arise out of the behaviour of (masses of) player-characters?
How do those change the game - through "accumulation", so to speak? That is, is a war effort like you described the sum of many many smaller, "ordinary" actions undertaken by players - or is there some sort of global change happening to the game itself, that is: within the software? Lemme dream something up: nasty posters appear on the walls, military police NPCs start looking for draft dodgers, the weather gets worse to support the atmosphere ;)? (Not these example-things in particular of course.)